Box Squats

What is the Law of Accommodations? In laymen's terms it means that doing too much of one thing will get you nowhere. We, as humans, are highly adaptable to our environment. Sometimes we need to shake things up in order to progress and move forward. Box squatting can be one method to rattle the tree.
So how do we box squat? Sit back, knees out, back arched, and head up. Ok, that was overly simplistic, but not really. When learning to box squat build from the bottom up, In this case the bottom being the lower body. We want to take a wide (a lot wider than shoulder width) stance and move the hips first and back so that we end up sitting on the box in a position that will allow the shins to be perpendicular to the ground (or slightly behind the heels if we're focusing on Glute/Ham strength). The knees are pushed outward and track over the feet. The back is arched and the head is neutral (looking straight ahead or slightly up). Pause at the bottom for a second or two and relax the hips, but nothing else. Then explode out of the hole by flexing hard with the hammies like you're performing a leg curl. Think "spread the ground apart" with the feet and knees instead of applying pressure straight into the ground. See, easy.
Don't get too hung up on the details. The bar should be place on the shoulders where it is "comfortable". If the bar is in an uncomfortable place for the lifter it will throw them off. The depth of the box will be based on the flexibility of the lifter. Ideally it will be 1-2 inches below parallel. Fill the abdomen with air (belly breath) before the start of the movement and hold it until you're standing again.
Keep repetitions and weight low while the sets can be higher. We're looking to improve explosive strength by moving the bar quickly. Once the bar stops moving quickly (either through too many reps or too much weight) we're wasting our time.
If done right (as with most things in life) box squatting is safe. One last thing to remember: most people sit on the toilet with better form than they squat with.